The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Oct. 18, 1994

Filed:

Dec. 09, 1992
Applicant:
Inventors:

Norio Komura, Tokyo, JP;

Hiroshige Makita, Tokyo, JP;

Tomoaki Ishikawa, Saitama, JP;

Taro Miyakawa, Tokyo, JP;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F16H / ;
U.S. Cl.
CPC ...
474 28 ; 474 18 ;
Abstract

A hydrostatic continuously variable transmission includes a closed hydraulic circuit comprising a hydraulic pump, a hydraulic motor, and an oil supply passage connected between the hydraulic pump and the hydraulic motor. The hydraulic pump selectively generates a first oil pressure lower than a first predetermined pressure level, a second slowly-changing oil pressure higher than the first predetermined pressure level when the transmission is in normal operation, and a third rapidly-changing oil pressure higher than a second predetermined pressure level higher than the first predetermined pressure level when the transmission starts to operate. The transmission also includes a first pressure-responsive valve for connecting the oil supply passage to the oil tank in response to the first oil pressure applied through the oil supply passage, and disconnecting the oil supply passage from the oil tank in response to the second oil pressure applied through the oil supply passage, and a second pressure-responsive valve for connecting the oil supply passage to the oil tank in response to the third oil pressure applied through the oil supply passage, and disconnecting the oil supply passage from the oil tank in response to the second oil pressure applied through the oil supply passage.


Find Patent Forward Citations

Loading…